Press brake



W. G. 'WEHR PRESS BRAKE May 7, 1940 7 2 Sheets-Sheet 1 Filed March 20, 1939 INVENTOR. MAL/am C1. Meme 8 Y j/mrmf W ATTORNEY45 y 1940- w. so WEH 29399 4 I PRESS BRAKE Filed March 20, 1959 2 Sheets-Sheet 2 -"2 fzi 48 5&5 48% 1N\ ENTOR. Mum/*1 G. IVE/we ATTORNEYS Patented May 7, 1940 UNITED STATES PATENT OFFlCE PRESS BRAKE 7 1 William G. Wehr, East Cleveland, Ohio, assignor to The Cleveland Crane a Engineering Company, Wickliffe, Ohio, a corporation of Ohio Application MarchZO, 1939, Serial No. 262,951

9 Claims. (Cl. 153-21) nection. In operation, the bed and ram deflect somewhat which causes the metal being bent not to be of the same angle from end to end and the object of the present invention is the provision of means for compensating for this deflection of the bed and/or ram.

Another object of the present invention is the provision of a novel press brake comprising means for adjusting the dies to compensate for deflection so that articles bent thereon will be of uniform angle from end to end.

Another object of this invention is the provision of an adjustable bolster block adapted to be interposed between a die of a brake press and its supporting member and adjusted to compensate for deflection in the bed and/or ram of the press so that articles bent thereon will be of uni form angle from end to end.

The present invention resides in certain details of construction and combinations and arrangements of parts and further objects and advantages thereof will be apparent to those skilled in the art to which the invention relates from the following description of the preferred embodiment thereof described with reference to the accompanying drawings forming a part of this specification, in which similar reference characters designate corresponding parts throughout the several views and in which:

Fig. l is a perspective View of a press brake embodying the present invention;

Fig. 2 is a sectional View through the upper portion of the lower leaf;

Fig. 3 is an enlarged view of the left-hand adjusting screw shown in. Fig. 2; I

Fig. 4 is an enlarged view of the right-hand adjusting screw shown in Fig. 2;

Fig. 5 is an enlarged view of the die-engaging portion of the adjustable bolster block shown in Figs. 1 and 2;

Fig. 6 is an end view of the member shown in Fig. 7 is an enlarged view of one of the wedges of the adjustable bolster block shown in Figs. 1 and 2; 1

. conventional construction.

brake illustrated is similar in construction to the ence characters in and Hi.

Fig. 8 is an end View of the wedge shown in Fig. 7;

Fig. 9 is an enlarged View of the lower member of the adjustable bolster block shown in Figs.

1 and 2;

Fig. ll] is an end View of the member shown in 9; I Fig. ll is a sectional View on the line ll--H of Fig. 2;

12 is an enlarged view of a portion of ll; 7

i3 is a sectional view similar to Fig. 2 but showing a modified construction; and,

Fig. 14 is a sectional view similar to Fig. 2 but,

leaf or ram C toward and from the lower leaf B.

The means for reciprocating the upper leaf C in the present instance comprises adjustable pitmans ill connected to the leaf C and to a crank shaft (not shown) extending along the top of the press brake. an electric-motor housed within the frame A and operatively connected to the crank shaft in a conventional manner by means including a clutch, the engagement of which is under the control of a foot treadle l l. The clutch is automatically disengaged upon one rotation of the crank shaft in a manner well understood in the art. The press brake thus far described may be of. any

press brake shown in U; S. patent to C. J. Bath, No. 1,997,672, issued April 16, 1935, and is known commercially by the trade name Steelweld.

The crank shaft is rotated by The particular press In Fig-1, the dies are designated by the refer- The upper die it is detachably secured to theunderside of the upper leaf 0 and the lower die It is positioned on an adjustable bolster block designated generally as D, which bolster block is in turn supported on a member ll welded to and forming a part of the tical reasons is usually not as deep as the upper The dies deflect with. the leaves and unless this deflection is compensated for the result is that the metal being bent is in the same angle from end'toend the embodiment of the in vention shown in Fig.1 deflection in the leaves is compensated for by the adjustable bolster block D. The height or thickness of any portion of the bolster block D can be varied to raise or lower that portion of the lower die I6 immediately thereabove. The maximum deflection usually, but not always, occurs adjacent the center of the dies, as it is usually the center portions of the dies which are supported by those parts of the leaves which are farthest removed from the leaf supports. In this event the bolster block or blocks are adjusted in a manner which will be apparent hereinafter to raise the center of the die or dies above the ends thereof. The leaves also deflect in proportion to the force applied thereto and by the adjustable compensating means of the present invention any condition can be readily compensated for.

The invention is particularly useful with press brakes of the larger size and where accurate work is required.

Referring particularly to Figs. 2 to 12, inclusive, the adjustable bolster block D shown therein comprises an upper member I8 adapted to directly support the die I6, a channel-shaped member I9 adapted to be positioned upon the die plate I I and within the channel of which the member I8 is located, and a plurality of wedge members and 2| positioned in the channel of the member I9 underneath the member I8. The underside of the member I9 is provided with a tongue 22 adapted to engage in a groove 23 in the upper surface of the die plate I! which prevents displacement thereof sidewise of the die plate IT. The wedge members 20 and 2I extend the full length of the bolster block and have tapered lower surfaces 25 and 26, respectively, which cooperate with reversely tapered surfaces 2? and 28 that form the bottom of the channel of the member I9. The construction is such that as the Wedge members 20 and 2! are moved transversely of the length of the bolster block, the member I8 is adjusted or moved vertically.

For the purpose of moving or adjusting the wedge members 20 and 2| transversely of the bolster block, a plurality of double screws designated generally as E are provided. The screws E are spaced longitudinally of the bolster block and afford means for adjusting any desired part or section of the wedge members. Each of the screws E comprises two axially aligned threaded members 38 and 3 I, the first of which has threaded engagement with a suitably tapped aperture in the wedge member 20 while the second has similar threaded engagement with the wedge member 2|. The inner or adjacent ends of the threaded members 30 and 3| abut and the members are caused to rotate as a unit by the engagement of a hexagonal projection 32 on the threaded member 3| within a hexagonal aperture 33 in the threaded member 30. Both members 30 and 3i are provided with heads 34 counterbored as at 35 to provide a driving connection for the engagement of a wrench of suitable construction adapted to be inserted through suitable apertures 36 in the flange of the member I9. The threaded members are so constructed that their overall length is the same as the width of the channel in the member I3 and the heads thereof abut or engage opposite walls of the channel, thus eliminating any lost motion. The screws E are made in two parts, as shown, to facilitate assembly and the hexagonal connec- .tion between the two threaded members 30 and 3I provides means for initially adjusting the wedge members 20 and 2| relative to each other.

In the embodiment of the invention shown, the

bolster block is 12 feet long and the adjusting screws E are located 12 inches apart, with the exception of the two end screws which are 11 inches apart, thus placing the first screw 1 inch from the end. The wedge members 20 and 2I are provided with a plurality of staggered transversely extending slots 31 and 38 opening into the outside and inside edges thereof. The depth and arrangement of these slots are such that the wedge members will flex intermediate the screws 'E. In the absence of these slots, the wedge members would flex at the screws since the portions adjacent to the screws would otherwise be the weakest portions due to the apertures therein within which the screws are threaded. Any desired number or arrangement of transverse slots may be employed. In the embodiment shown, comparatively deep slots 38 are provided opening into the inside edges of the wedge members and located half way between each of the screws E. The opposite sides of the wedge members are provided with'two slots 31 between each screw E, which slots are of equal depth and are equally spaced between the screws and the deeper slot 38 in the other side of the wedge member. The construction shown gives the greatest bending adjacent to the slots 31 farthest remote from the particular screw being adjusted but within' For example, when:

the next adjacent screws. the screw E is rotated, the maximum bending in the wedge members occurs adjacent to the slots 31 as these slots are farthest from the screw E but Within the two adjacent screws E.

With the construction shown, any desired section of the member I8 and in turn the die positioned thereon, can be adjusted vertically to compensate for any deflection in that portion of the leaf or die. ()rdinarily the greatest deflection comes midway between the ends of the leaf which ne- The screws E provide a micrometer adjustment as the deflection in the leaves of a press brake is measured in thousandths of an inch. The cooperating inclined surfaces in practice are of a very low angle so as to minimize the force applied to the screws in operation. For purposes of illustration, the angle of the wedge surfaces has been exaggerated. The bolster block shown in Figs. 1 to 12, inclusive, gives a maximum adjustment of one-thirty-second of an inch. Any portion of the bolster block may be raised or lowered above or below any other portion of the bolster block and in turn that portion of the die 1 immediately thereabove will be raised or lowered accordingly.

A modified construction of the preferred embodiment of bolster block just referred to is illustrated in Fig. 13. As shown in this figure,

the upper member 40 is channel-shaped and the Aside from this difference, the conlar in construction to the upper member shown in Fig. 13 and is held from displacement sidewise of the die plate I? by side members 44 and 45 welded thereto which project down over the die plate I1". 'In Fig. 14 the parts which are similar to those shown in Figs. 1 to 12, inclusive, are designated by the same reference characters with a double prime mark affixed thereto.

As shown, the invention has been embodied in bolster blocks adapted to be removably positioned on the die plate of the lower leaf of a brake press. This construction is preferred because the adjustable bolster block can then be removed when the brake press is used on rough work, etc. However, it is to be understood that the adjusting means shown can be built into the lower leaf as an integral part thereof, if desired. It is also to be understood that while the adjustment 'has been shown as applied to the lower leaf, the present invention contemplates its application to the upper leaf or ram of a press brake.

While the preferred embodiment of the invention has been described with considerable detail, I do not wish to be limited'to the particular constructions shown which may be varied within the scope of this invention and it is my intention to cover hereby all adaptations and modifications and arrangements thereof which come within the practice of those skilled in the art to which the invention relates and I particularly point out and claim as my invention the following:

1. A bolster block adapted to be interposed between the die of a press brake and one of the leaves thereof, said bolster block comprising a vertically movable. member, means for securing said vertically movable member against sidewise displacement relative to the leaf with which it is used, and wedge means for vertically adjusting portions of said member relative to said leaf.

2. A bolster block adapted to be interposed between the die of a press brake and one of the leaves thereof, said bolster block comprising a vertically movable member, means for securing said member against s-idewise displacement relative to the leaf with which it is used, and means for adjusting portions of said member in a vertical direction relative to said leaf, said last-mentioned means comprising a plurality of longitudinally extending Wedge members and means for moving said wedge members transversely of the length of the bolster block to adjust said movable member vertically;

3. A bolster block adapted to be interposed between the die of a press brake and one of the leaves thereof, said bolster block comprising a vertically movable member, means for securing said member against sidewise displacement relative to the leaf with which it is used, and means for adjusting portions of said member in a vertical direction relative to said leaf, said last-mentioned means comprising a plurality of longitudinally extending wedge members and a plurality of longitudinally spaced screws having threaded engagement with said wedge members for moving portions of said wedge members transversely of the length of said bolster to adjust the movable member vertically, said wedge members having transversely extending slots intermediate said screws.

relatively movable members, a plurality of longitudinally extending wedge members interposed between said relatively movable members, and means for moving portions of said wedge members transversely of the length of the bolster block while other portions thereof remain stationary to relatively adjust portions of said movable members vertically relative to other portions thereof.

6. A bolsterblock adapted to be interposed between the die. of a press brake and one of the leaves thereof, said bolster block comprising two relatively movable members, a plurality of longitudinally extending wedge members interposed between said two relatively movable members, and a plurality of longitudinally spaced screws having threaded engagement with said wedge member's for'moving transversely of the length of said bolster block portions of said wedge members relative to other portions thereof to relatively adjust portions of the two movable members vertically, said wedge members having transversely extending slots intermediate said screws.

7. In a press brake of the character described, the combination of a frame, a lower leaf including a die, an upper leaf including a die, means for producing relative reciprocation between said leaves to open and close said dies, and wedge means for adjusting portions of one of said dies relative to other portions thereof and to its respective leaf.

8. In a press brake of the character described, the combination of a frame, a lower leaf including a die, an upper leaf including a die, means for producing relative reciprocation between said leaves to close and open said dies, a plurality of longitudinally extending wedge members positioned underneath one of said dies, and means for moving portions of said wedge members transversely of the die to adjust portions of the die vertically to compensate for deflection in operation.

9. In a press brake of the character described, the combination of a frame, a lower leaf including a die, an'upper leaf including a die, means for producing relative reciprocation between said leaves to close and open said dies, a plurality of longitudinally extending wedge members positioned underneath one of said dies, and a plurality of longitudinally spaced screws having threaded engagement with said wedge members for moving portions thereof transversely of the length of said die to adjust portions of the die immediately thereabove vertically to compensate for deflection in operation, said wedge members having transversely extending slots intermediate said screws.

WILLIAM G. WEI-1R. 

